Move NumberToStringStub::GenerateLookupNumberStringCache to the MacroAssembler.

src/x64/macro-assembler-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2246 matching lines @@
 
 
 void MacroAssembler::Test(const Operand& src, Smi* source) {
   testl(Operand(src, kIntSize), Immediate(source->value()));
 }
 
 
 // ----------------------------------------------------------------------------
 
 
+void MacroAssembler::LookupNumberStringCache(Register object,
+                                             Register result,
+                                             Register scratch1,
+                                             Register scratch2,
+                                             Label* not_found) {
+  // Use of registers. Register result is used as a temporary.
+  Register number_string_cache = result;
+  Register mask = scratch1;
+  Register scratch = scratch2;
+
+  // Load the number string cache.
+  LoadRoot(number_string_cache, Heap::kNumberStringCacheRootIndex);
+
+  // Make the hash mask from the length of the number string cache. It
+  // contains two elements (number and string) for each cache entry.
+  SmiToInteger32(
+      mask, FieldOperand(number_string_cache, FixedArray::kLengthOffset));
+  shrl(mask, Immediate(1));
+  subq(mask, Immediate(1));  // Make mask.
+
+  // Calculate the entry in the number string cache. The hash value in the
+  // number string cache for smis is just the smi value, and the hash for
+  // doubles is the xor of the upper and lower words. See
+  // Heap::GetNumberStringCache.
+  Label is_smi;
+  Label load_result_from_cache;
+  JumpIfSmi(object, &is_smi);
+  CheckMap(object,
+           isolate()->factory()->heap_number_map(),
+           not_found,
+           DONT_DO_SMI_CHECK);
+
+  STATIC_ASSERT(8 == kDoubleSize);
+  movl(scratch, FieldOperand(object, HeapNumber::kValueOffset + 4));
+  xor_(scratch, FieldOperand(object, HeapNumber::kValueOffset));
+  and_(scratch, mask);
+  // Each entry in string cache consists of two pointer sized fields,
+  // but times_twice_pointer_size (multiplication by 16) scale factor
+  // is not supported by addrmode on x64 platform.
+  // So we have to premultiply entry index before lookup.
+  shl(scratch, Immediate(kPointerSizeLog2 + 1));
+
+  Register index = scratch;
+  Register probe = mask;
+  movq(probe,
+       FieldOperand(number_string_cache,
+                    index,
+                    times_1,
+                    FixedArray::kHeaderSize));
+  JumpIfSmi(probe, not_found);
+  movsd(xmm0, FieldOperand(object, HeapNumber::kValueOffset));
+  ucomisd(xmm0, FieldOperand(probe, HeapNumber::kValueOffset));
+  j(parity_even, not_found);  // Bail out if NaN is involved.
+  j(not_equal, not_found);  // The cache did not contain this value.
+  jmp(&load_result_from_cache);
+
+  bind(&is_smi);
+  SmiToInteger32(scratch, object);
+  and_(scratch, mask);
+  // Each entry in string cache consists of two pointer sized fields,
+  // but times_twice_pointer_size (multiplication by 16) scale factor
+  // is not supported by addrmode on x64 platform.
+  // So we have to premultiply entry index before lookup.
+  shl(scratch, Immediate(kPointerSizeLog2 + 1));
+
+  // Check if the entry is the smi we are looking for.
+  cmpq(object,
+       FieldOperand(number_string_cache,
+                    index,
+                    times_1,
+                    FixedArray::kHeaderSize));
+  j(not_equal, not_found);
+
+  // Get the result from the cache.
+  bind(&load_result_from_cache);
+  movq(result,
+       FieldOperand(number_string_cache,
+                    index,
+                    times_1,
+                    FixedArray::kHeaderSize + kPointerSize));
+  IncrementCounter(isolate()->counters()->number_to_string_native(), 1);
+}
+
+
 void MacroAssembler::JumpIfNotString(Register object,
                                      Register object_map,
                                      Label* not_string,
                                      Label::Distance near_jump) {
   Condition is_smi = CheckSmi(object);
   j(is_smi, not_string, near_jump);
   CmpObjectType(object, FIRST_NONSTRING_TYPE, object_map);
   j(above_equal, not_string, near_jump);
 }
 
@@ skipping 2556 matching lines @@
   j(greater, &no_memento_available);
   CompareRoot(MemOperand(scratch_reg, -AllocationMemento::kSize),
               Heap::kAllocationMementoMapRootIndex);
   bind(&no_memento_available);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64